package 牛客周赛.牛客周赛Round82;

import java.util.Scanner;

/**
 * @Title: A
 * @Author 贾金博
 * @Package 牛客周赛.牛客周赛Round82
 * @Date 2025/4/8 上午10:33
 * @description: This is A
 */
public class A {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        char a = sc.next().charAt(0);
        if(a == 'U' || a == 'D') {
            System.out.println('R');
        } else {
            System.out.println('U');
        }
    }
}
